A braking system is disclosed. The braking system may include a controller configured to determine a speed threshold that is based on a deceleration of an output speed of a powertrain of a machine caused in part by engagement of one or more brakes of the machine during a directional shift in a movement of the machine, the speed threshold being the output speed of the powertrain at which the one or more brakes are to be commanded to disengage. The controller may be configured to command disengagement of the one or more brakes based on a determination that the output speed of the powertrain satisfies the speed threshold.

A method of brake steering in a four-wheel drive utility vehicle having a driven front axle carrying at least two front wheels, a driven rear axle carrying at least two rear wheels, a powertrain delivering torque to the front axle via a first motor and to the rear axle via a second motor, a controlled clutch arrangement operable to couple the outputs of the first and second motors to vary the distribution of delivered torque between the front and rear axles, and independently operable service brakes on each of the front and rear wheels. The method includes determining a difference in wheel velocity between front and rear wheels; comparing the difference to a threshold value and, when exceeded, automatically engaging the controlled clutch arrangement. A determination is made as to whether or not the vehicle is performing a brake steering manoeuvre and the threshold value is adjusted accordingly. Additional braking force may be applied from independently operable park brakes on the rear wheels in inverse relationship to the level of service brake force applied.

A hydraulic device includes a braking device to brake a traveling device and release braking of the traveling device, a traveling pump to drive the traveling device with pressure of operation fluid, a brake-operation valve to control operation fluid flowing to the brake device, a traveling operation valve to control operation fluid flowing to the traveling pump, a first discharge fluid tube to discharge operation fluid flowing through the brake-operation valve, the first discharge fluid tube being connected to the brake operation valve, and a second discharge fluid tube to discharge operation fluid flowing through the traveling operation valve, the second discharge fluid tube being connected to the traveling operation valve. The traveling operation valve has a set pressure that is set to be higher than a brake set pressure set by the brake operation valve.

A progressive brake steering system that includes a steering shaft, a steering arm attached to the steering shaft and a spring mechanism that couples the steering arm to a first actuation pushrod of a first brake master cylinder and a second actuation pushrod of a second brake master cylinder. Rotating the steering shaft in a first direction rotates a first side of the steering shaft towards a first spring of the spring mechanism to compress the first spring against the first actuation pushrod of the first brake master cylinder to generate a first brake fluid pressure. Rotating the steering shaft in a second direction rotates a second side of the steering shaft towards a second spring of the spring mechanism to compress the second spring against the second actuation pushrod of the second brake master cylinder to generate a second brake fluid pressure.

A drive and control system for a lawn tractor includes a CAN-Bus network, a vehicle controller, a pair of hydrostatic or electric transaxles controlled by respective electronic drive controllers, and one or more steering and drive input devices coupled to respective sensor(s) for sensing user steering and drive inputs. The vehicle controller communicates with one or more vehicle sensors and one or more vehicle controllers that control one or more vehicle components via the CAN-Bus network. The vehicle controller processes the user's steering and drive inputs and posts on the CAN-Bus network digital drive signals configured to obtain the desired speed and direction of motion of the lawn tractor. The electronic drive controllers convert the digital drive signals to appropriate signals for driving the hydrostatic transaxles or the electric transaxles, as equipped, based on tunable motion parameters to obtain the desired speed and direction of motion of the lawn tractor.

A drive and control system for a lawn tractor includes a CAN-Bus network, a vehicle controller, a pair of hydrostatic or electric transaxles controlled by respective electronic drive controllers, and one or more steering and drive input devices coupled to respective sensor(s) for sensing user steering and drive inputs. The vehicle controller communicates with one or more vehicle sensors and one or more vehicle controllers that control one or more vehicle components via the CAN-Bus network. The vehicle controller processes the user's steering and drive inputs and posts on the CAN-Bus network digital drive signals configured to obtain the desired speed and direction of motion of the lawn tractor. The electronic drive controllers convert the digital drive signals to appropriate signals for driving the hydrostatic transaxles or the electric transaxles, as equipped, based on tunable motion parameters to obtain the desired speed and direction of motion of the lawn tractor.

An emergency stop brake operation assembly necessary for a work vehicle when travelling autonomously in an unmanned state is provided in this brake system without introducing problems to manual driving of the work vehicle by an occupant. This brake system for work vehicles comprises: a brake pedal that is disposed in a driving section; a brake that brakes left and right rear wheels; a linkage mechanism that links the brake pedal and the brake in such a manner as to allow the brake pedal and the brake to operate in conjunction with each other; and an electric brake operating device that actuates the brake in response to an emergency stop command. The brake operating device has: an operation-receiving body that is coupled to the brake pedal; an electric actuator that operates the operation-receiving body; and a clearance-provided section which is located between the brake pedal and the electric actuator and allows displacement of the brake pedal and the linkage mechanism with respect to the electric actuator when the brake pedal is depressed.

Provided is a parking brake apparatus for a vehicle that allows an improvement in the ease of assembly. A parking brake apparatus includes a valve, a single hydraulic actuator that includes a cylinder, a piston housed in the cylinder in such a manner as to be reciprocably displaceable along the cylinder, and a principal brake rod connected to the piston, and can displace the piston to one of a brake operating position and a brake non-operating position by the valve, a balance arm connected to a first end portion of the principal brake rod on a side protruded from the cylinder, and a pair of left and right auxiliary brake rods provided between bent portions at end portions of the balance arm and left and right brake arms, respectively. The hydraulic actuator includes a spring member for constantly urging the piston to the brake operating position.

A differentially steered vehicle includes brakes on the powered wheels which are applied via a controller according to different methods to inhibit freewheeling during turns and improve steering responsiveness and stability. The methods include applying braking force to the wheel on the inside of a turn in response to the rate of turn as indicated by the position of the steering control, to the pressure differential across the hydraulic motors driving the wheels and the rotational speed of the wheels.

A riding lawn care vehicle includes a frame to which at least a first and second drive wheels are attachable. The vehicle further includes a brake assembly operably coupled to the first and second drive wheels to enable brakes to be selectively applied to the first and second drive wheels. The riding lawn care vehicle also includes a steering assembly with first and second steering levers. First and second steering levers are operably coupled to first and second drive wheels respectively to facilitate turning of the riding lawn care vehicle based on drive speed control of the first and second drive wheels responsive to positioning of first and second steering levers. First and second steering levers are also operably coupled to the brake assembly to activate the brake assembly in response to one of the first or second steering levers being rotated about a vertical axis of the respective lever.